1. Field of the Invention
The present invention relates to a freight car for incorporation into a freight train of a series of successively arranged like freight cars, successive ones of the freight cars having facing ends which may be coupled together to form the train. The freight car is of the known type comprising a longitudinally extending carrier frame, a longitudinally extending box for storing bulk material, the box having a bottom affixed to the carrier frame and an open top, and a longitudinally extending bulk material conveyor arrangement arranged at least partly along the bottom of the box, the conveyor arrangement having opposite ends longitudinally spaced from each other and one of the conveyor arrangement ends being higher than the opposite conveyor arrangement end whereby the conveyor arrangement ends at facing ends of the successive freight cars overlap when the freight cars are coupled together.
2. Description of the Prior Art
Such a freight car has been disclosed in U.S. Pat. No. 4,576,538, dated Mar. 18, 1986. As described in the patent, when such box cars are coupled together to form a train, the successive conveyor arrangements constitute a continuous conveyor path along the length of the train so that bulk material thrown into the box at one end of the train can be conveyed without further equipment to the box at the opposite end of the train for storing. In this way, the box cars can be successively filled.
U.S. Pat. No. 3,842,994, dated Oct. 22, 1974, also discloses a train of like freight cars with funnel-shaped boxes for storing bulk material. Two conveyor bands are mounted above the open top of each bulk material storage box and these conveyor bands are longitudinally displaceable relative to each other. The ends of adjacent conveyor bands overlap so that the bulk material can be transported from car to car. Bulk material stored in the boxes is discharged therefrom through discharge chutes in the side walls of the boxes. The conveying and discharge arrangements are relatively complex.
Finally, German patent application No. 3,420,836, published Dec. 13, 1984, discloses a track working machine for removing old ballast and providing new ballast. The machine comprises a train of freight cars for storing bulk material, i.e. ballast, each car having endless conveyor bands extending longitudinally along its sides for conveying the ballast. Such freight cars require special loading equipment for charging each conveyor band with the ballast to be conveyed.